/* Browsing pages: the tracks and all lessons. Same ground, type, pattern and footer as the home page (engine/home.css). */
:root {
  --bg: #0B211B; --panel: #0F2B23; --ink: #EEF3EE; --muted: #A9C0B5; --line: #1F3E34; --accent: #D08A4E; --amber: #FFC857; --mat: #2E6E55; --sand: #C2AE74; --dark: #10140F;
  --font-display: "Space Grotesk", "Segoe UI", system-ui, sans-serif; --font-body: "IBM Plex Sans", "Segoe UI", system-ui, sans-serif;
  --pat: #D08A4E; --pato: .16; --m: clamp(16px, 4vw, 56px); color-scheme: dark;
}
@media (prefers-color-scheme: light) { :root:not([data-theme="dark"]) { --bg: #EEF0EA; --panel: #E2E7DF; --ink: #0F241C; --muted: #45594F; --line: #CBD3C8; --accent: #B8692E; --pat: #0E5B43; --pato: .13; color-scheme: light; } }
:root[data-theme="light"] { --bg: #EEF0EA; --panel: #E2E7DF; --ink: #0F241C; --muted: #45594F; --line: #CBD3C8; --accent: #B8692E; --pat: #0E5B43; --pato: .13; color-scheme: light; }
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 17px/1.55 var(--font-body); -webkit-font-smoothing: antialiased; overflow-x: clip; }
body::before { content: ""; position: fixed; inset: 0; z-index: 0; pointer-events: none; background: var(--pat); opacity: var(--pato);
  -webkit-mask: url(pcb.svg) 0 0 / 480px 480px repeat; mask: url(pcb.svg) 0 0 / 480px 480px repeat; }
.wrap, .foot { position: relative; z-index: 1; }
a { color: var(--accent); }
:focus-visible { outline: 3px solid var(--amber); outline-offset: 3px; }
.wrap { max-width: 1200px; margin: 0 auto; padding: 24px var(--m) 96px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: inherit; text-decoration: none; }
.brand svg { width: 32px; height: 32px; color: var(--accent); }
.brand b { display: block; font: 700 18px/1.1 var(--font-display); }
.brand small { display: none; }
h1 { font: 700 clamp(36px, 6vw, 76px)/1 var(--font-display); letter-spacing: -.035em; margin: 56px 0 16px; max-width: 18ch; text-wrap: balance; }
h2 { font: 700 clamp(24px, 2.6vw, 34px)/1.1 var(--font-display); letter-spacing: -.02em; margin: 56px 0 6px; }
h2 a { color: inherit; text-decoration: none; } h2 a:hover { color: var(--accent); }
.lead { color: var(--muted); max-width: 56ch; margin: 0 0 32px; font-size: 18px; }
.sub { color: var(--muted); margin: 0 0 16px; max-width: 70ch; }
.crumbs { color: var(--muted); font-size: 15px; margin: 28px 0 0; }
.crumbs a { color: var(--ink); }
.feature { display: grid; grid-template-columns: 1fr; background: var(--panel); border-radius: 28px; overflow: hidden; text-decoration: none; color: inherit; transition: transform .25s cubic-bezier(.2, .7, .2, 1); }
.feature:hover { transform: translateY(-3px); }
.feature .mat { background: var(--mat); background-image: linear-gradient(rgba(214,240,226,.3) 1px, transparent 1px), linear-gradient(90deg, rgba(214,240,226,.3) 1px, transparent 1px); background-size: 24px 24px; min-height: 160px; display: grid; place-items: center; color: #EEF3EE; font: 700 64px var(--font-display); }
.feature .txt { padding: 22px 26px 26px; display: grid; gap: 6px; }
.feature .eyebrow { font: 600 13px var(--font-display); color: var(--accent); }
.feature b { font: 700 26px/1.15 var(--font-display); letter-spacing: -.02em; }
.feature span:last-child { color: var(--muted); }
@media (min-width: 720px) { .feature { grid-template-columns: 300px 1fr; } .feature .txt { align-self: center; } }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 10px; }
.lsn { display: grid; grid-template-columns: auto 1fr auto; gap: 14px; align-items: center; background: var(--panel); border-radius: 18px; padding: 14px 16px; color: inherit; text-decoration: none; min-height: 56px; transition: transform .2s cubic-bezier(.2, .7, .2, 1); }
.lsn .no { width: 40px; height: 40px; border-radius: 50%; display: grid; place-items: center; font: 700 13px var(--font-display); color: var(--ink); border: 4px solid var(--accent); background: var(--bg); }
.lsn .tx b { display: block; font: 600 16px/1.3 var(--font-display); }
.lsn .tx small { display: block; color: var(--muted); font-size: 13.5px; line-height: 1.4; margin-top: 2px; }
.lsn .st { font: 600 13px var(--font-display); color: var(--muted); }
.lsn.live .st { color: var(--accent); }
.lsn.live:hover { transform: translateY(-2px); } .lsn.live:hover .tx b { color: var(--accent); }
.lsn:not(.live) { opacity: .6; } .lsn:not(.live) .no { border-color: var(--line); }
.filters { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 20px; }
.filters input, .filters select { font: inherit; font-size: 16px; padding: 10px 16px; border: 2px solid transparent; border-radius: 999px; background: var(--panel); color: var(--ink); min-height: 48px; }
.filters input:focus, .filters select:focus { border-color: var(--accent); outline: none; }
.filters input { flex: 1 1 240px; }
@media (max-width: 760px) { h1, .lead, .crumbs { text-align: center; margin-left: auto; margin-right: auto; } h2 { text-align: center; } .sub { text-align: center; margin-left: auto; margin-right: auto; } .wrap > .brand { display: flex; justify-content: center; } }

/* the footer, as on the home page: the name built from blocks */
.btn { display: inline-flex; align-items: center; gap: 12px; min-height: 44px; padding: 0 24px 0 16px; border-radius: 999px; font: 600 15px var(--font-display); text-decoration: none; background: var(--bg); color: var(--ink); transition: transform .18s; }
.btn i { width: 14px; height: 14px; border-radius: 50%; border: 4px solid var(--accent); background: var(--bg); flex: none; }
.btn:hover { transform: translateY(-2px); }
.foot { background: var(--panel); padding: 56px var(--m) 32px; }
.mark { display: flex; gap: 4px; align-items: flex-end; height: 34svh; min-height: 200px; text-decoration: none; }
.mark span { flex: 1; height: var(--h); display: flex; align-items: flex-end; justify-content: center; border-radius: 6px 6px 0 0; font: 700 min(12vw, 30svh)/.78 var(--font-display); color: var(--panel); overflow: hidden; transition: height .5s cubic-bezier(.2, .7, .2, 1); }
.mark span:nth-child(4n+1) { background: var(--accent); } .mark span:nth-child(4n+2) { background: var(--mat); } .mark span:nth-child(4n+3) { background: var(--sand); } .mark span:nth-child(4n) { background: var(--amber); }
.mark:hover span { height: calc(var(--h) * .92 + 8%); }
.links { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 24px; margin-top: 56px; }
.links nav { display: grid; gap: 4px; align-content: start; }
.links a { font-size: 15px; text-decoration: none; min-height: 32px; display: flex; align-items: center; color: var(--ink); }
.links a:hover { color: var(--accent); }
.last { display: flex; justify-content: space-between; align-items: center; gap: 16px; margin-top: 48px; flex-wrap: wrap; }
.last p { margin: 0; font-size: 15px; color: var(--muted); max-width: 52ch; }
@media (max-width: 760px) { .mark { height: 22svh; min-height: 140px; } .mark span { font-size: 13vw; } .links { grid-template-columns: 1fr 1fr; } }
@media (prefers-reduced-motion: reduce) { * { transition: none !important; } }